Medulloblastoma: treatment technique and radiation dosimetry

Journal Article · Sat Jan 01 00:00:00 EST 1977 · Int. J. Radiat. Oncol., Biol. Phys.; (United States)

DOI:https://doi.org/10.1016/0360-3016(77)90202-4· OSTI ID:5089878

Van Dyk, J; Jenkin, R D.T.; Leung, P M.K.; Cunningham, J R

It is well established that elective cranio-spinal irradiation is beneficial in the treatment of medulloblastoma. However, because of the geometry of the brain and the spinal column, a simple treatment procedure which results in a uniform dose over the entire target volume while maintaining a low dose to other tissues is not easy to perform. This report describes a relatively simple treatment technique which can be administered with radiotherapy apparatus that is available in most treatment centers. Special consideration is given to the dosimetry in the junction regions of the contiguous /sup 60/Co fields. Computer dosage calculations were made to check the effectiveness of this technique. This calculated data was verified experimentally with thermoluminescent dosimetry (TLD) in both a rectangular polystyrene phantom as well as the human like Alderson Rando phantom. The dose to critical organs such as the eyes was found to be less than 15 percent of the tumor dose, while the male gonadal dose was less than 10 percent. Detailed consideration is given to the factors affecting the overall variation of dose in the entire target volume. It has been estimated that using this technique, the overall dosage variation to the cranio-spinal axis is within +-10 percent of the prescribed tumor dose for the average adult, while for the average child it is better than +-5 percent.

• Research Organization: Ontario Cancer Inst., Toronto
• OSTI ID: 5089878
• Journal Information: Int. J. Radiat. Oncol., Biol. Phys.; (United States), Vol. 2:9/10
• Country of Publication: United States
• Language: English

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63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
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RADIOTHERAPY
EYES
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GONADS
DOSIMETRY
PLANNING
SPINAL CORD
COBALT 60
GAMMA RADIATION
NEOPLASMS
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INTERNAL CONVERSION RADIOISOTOPES
IONIZING RADIATIONS
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
MEDICINE
MINUTES LIVING RADIOISOTOPES
NERVOUS SYSTEM
NUCLEAR MEDICINE
NUCLEI
ODD-ODD NUCLEI
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560151* - Radiation Effects on Animals- Man